Steering arrangement for outboard propulsion unit



June 9, 1964 E. c. KIEKHAEFER 3,136,285

STEERING ARRANGEMENT FOR oUTBoARD PRoPULsIoN UNIT Filed Jan. 7, 1963 2 Sheets-Sheet l s.. will 1N. m K

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June 9 1964 E. c. KlEKHAl-:FER 3,136,285

STEERING ARRANGEMENT FOR OUTBOARD PROPULSION UNIT Filed Jan. fr, 1965 INVENTOR 51m-A C zfxunfffk BY 7j? 4 ,wm ff 5MM.

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United States Patent O 3,136,285 STEERING ARRANGEMENT FOR OUTBOARD PROPULSION UNIT Elmer Carl Kiekhaefer, Winter Haven, Fla., assignor t Kiekhaefer Corporation, Fond du Lac, Wis., a corporation of Delaware Filed Jan. 7, 1963, Ser. No. 249,641 Claims. (Cl. 115-35) This invention relates to the steering arrangement for an outboard propulsion unit of an inboard-outboard drive.

Outboard or stern drive units are generally pivoted for steering by steering control means actuated from a remote location in the watercraft. The steering control means are frequently connected to the drive unit externally of the watercraft and extend through a transom opening spaced to one side or above the mounting plates for the drive unit. Not only does the additional opening for the control means tend to weaken the transom, but it also presents another possible source of leakage into the watercraft. Then, too, the control means passing through the transom and exposed rearwardly thereof are unsightly and unprotected from corrosion and possible damage. Accordingly, it is generally an object of this invention to provide a steering arrangement which utilizes the stern drive mounting opening and wherein the control means remain wholly inside the boat and are protected from damage and corrosion.

The invention contemplates a stern drive unit wherein the transom support plate structure is properly aligned with respect to a transom mounting opening and is rigidly secured to the transom. The transom plate structure pivotally carries an intermediate member rearwardly and outboard of the transom for pivotal movement on a generally vertical axis for steering control of the unit. The stern drive unit is in turn pivotally supported by the intermediate member on a generally transverse horizontal axis to provide for tilt movements of the unit in a vertical plane.

Generally according to this invention, the transom plate structure includes an enclosure outboard of the transom and in alignment with the steering axis. The enclosure opens forwardly and communicates with the interior of the watercraft through the transom mounting opening. The generally vertical steering shaft on the intermediate member extends into the bore of the enclosure and is rotatably disposed therein. A steering arm for turning the shaft to provide for steering control of the stern drive unit is secured on the steering shaft within the enclosure and extends forwardly through the transom mounting opening and into the interior of the watercraft. The inboard end of the steering arm is adapted for connection to a push-pull means operable from a remote location in the watercraft to pivot the propulsion unit for steering.

The drawings furnished herewith illustrate the best mode for carrying out the invention as presently contemplated and set forth hereinafter.

In the drawings:

FIGURE l is a perspective view of a stern drive unit of an inboard-outboard drive mounted on a partially shown transom of a watercraft;

FIG. 2 is an enlarged elevational view in section of the outboard drive unit of an inboard-outboard drive shown mounted on a watercraft;

FIG. 3 is an enlarged view taken generally on line 3-3 of FIG. 2 and further shows a means for actuating the steering arm from a remote location within a watercraft; and

FIG. 4 is a view taken generally on line 4-4 of FIG. 2.

3,136,285 Patented June 9, 1964 ICS Referring to the drawings, the inboard-outboard drive includes a stern drive unit 1 mounted on the transom 2 of a partially shown boat or other watercraft 3. The stern drive unit includes a propeller 4 which is carried rearwardly on the generally horizontal propeller shaft 5 driven by the generally vertical drive shaft 6 through the drive gear 7 on shaft 6 spaced forward and reverse dliliven gears 8 and 9 freely rotatable on the propeller s aft.

The propeller 4 is rotatable in opposite directions for forward and reverse propulsion in accordance with selective engagement of the driven gears 8 and 9 by the axially movable clutch element 10 rotatably carried by the propeller shaft 5 between the driven gears. Axial movement of clutch element 10 is effected by the vertically disposed rotatable control rod 11 which carries the cam 12 at the lower end thereof for engagement with the axially movable spring-biased pin means 13 carrying the clutch element and projecting from the forward end of the propeller shaft 5. The rod 11 and cam 12 are rotatable by means not shown to selectively shift the clutch element 10 into engagement with gears 8 and 9 or into an intermediate neutral position.

The vertical drive shaft 6 is driven by the engine 14 mounted inboard of watercraft 3 through the horizontal drive shaft 15 extending through the transom and meshing bevel gears 16 and 17 carried on shafts 6 and 15 respectively. The horizontal drive shaft 15 includes a double universal joint 18 having its center substantially at the intersection of the generally vertical steering axis and generally horizontal tilt axis of the stern drive unit 1 as will be more fully described hereinafter.

The stern drive unit 1 is supported from the transom 2 by an inner transom plate 19 and outer transom plate 20 disposed on opposed sides of the transom. The transome plates 19 and 20 overlie the single transom opening 21 and are secured to each other and to the transom by means of suitable bolts 22.

The inner transom plate 19 includes a pair of transversely spaced forwardly extending arms 23 and 24 providing mounting support for the rear end of engine 14 and is provided with an upper steering arm opening 25, a lower opening 26 for the llexible engine exhaust conduit 27, and an opening 28 axially aligned with the engine shaft 29 carrying flywheel 30. The openings 25, 26 and 28 all communicate with the single transom opening 21.

The outer transom plate 20 includes a generally tubular pilot projection 31 which is outwardly stepped rearwardly thereof to provide a retaining well 32 for the ball bearing 33 rotatably supporting the Ihorizontal drive shaft 15. The pilot projection 31 is telescopically received by the opening 28 in the inner transom plate 19 to provide for proper alignment between drive shaft 15 and coupling element 34 carried by the engine flywheel 30.

Transom plate 20 further includes a tubular exhaust pipe 35 in alignment with opening 26 of the inner transom plate 19 and communicating with the engine exhaust pipe, not shown, through the flexible conduit 27. The exhaust gases from the engine 14 are delivered to the stern drive unit, for discharge under water, through the flexible bellows conduit 36 connecting the pipe 35 and the stern drive exhaust inlet 37 generally aligned with pipe 35.

A gimbal ring member 38 is disposed intermediate the outer transom plate 20 and the stern drive unit 1 and extends around the jointed drive shaft 15. The gimbal ring member 38 is adapted to receive therewithin the forward portion of the bell housing 39 of the stern drive unit for pivotal support of the unit on a pair of transversely spaced pin members 40 carried by the gimbal ring member and disposed on the generally transverse horizontal tilt axis. The tilt axis is generally disposed at the line of intersection of the transverse vertical and horizontal central planes through the double universal joint 18 in drive shaft 15 so that the drive can bend readily at the joint to accommodate tilt movements of the unit in a generally vertical plane. The trim or normal running position of the stern drive unit is determined by engagement of the unit with a tilt adjustment pin 41 removably disposed in a corresponding pair of a series of holes 42 in the transversely spaced yoke arms 43 carried at the lower end of the gimbal ring member 38.

The gimbal ring member 38 is in turn pivotally supported from the outer transom plate 20 by the axially spaced and aligned shaft elements 44 and 45 disposed on a generally vertical swivel axis for rotation of the gimbal ring together with the stern drive unit in a generally horizontal plane for steering control of the unit. Through preference the shaft elements 44 and 45 are disposed at a slight forward rake with their common axes passing generally through the center of the double universal joint 18 at the axis of shaft so that the drive bends correspondingly at the joint to accommodate steering movements of the unit.

The lower swivel shaft element 45 extends through a central bore 46 in the lower portion of the gimbal ring member 38 disposed between vertically spaced yoke arms 47 and 48 projecting rearwardly from the lower portion of the outer transom plate 20. Shaft element 45 extends through aligned holes 49 and 50 in the vertically spaced yoke arms 47 and 48 and is secured in place by means of an arcuate key member 51 disposed between the shaft element and lower yoke arm 48. The needle bearing 52 in the bore opening 46 rotatably supports the gimbal ring member 38 on shaft element 45.

The upper swivel shaft element 44 is carried by the upper portion of the gimbal ring member 38 in alignment with bore opening 46 in the lower portion of the ring member and extends upwardly into the generally vertically spaced and aligned bore openings 53 and 54 of the steering arm enclosure 55 forming an integral part of the outer transom plate 20. Shaft element 44 is disposed for rotation within the bore openings 53 and 54 as provided for by needle bearings 56 and 57 respectively. Thus, the gimbal ring 38 together with the stern drive unit 1 are rotationally supported for movement in a generally horizontal plane by the vertically spaced and aligned shaft elements 44 and 45.

The transom plate enclosure 55 communicates with openings 21 and 25 in transom 2 and inner transom plate 19 respectively through an opening 58 forwardly of the enclosure. A steering control arm 59 is secured on the shaft element 44 intermediate the bore openings 53 and 54 within enclosure 55 and extends forwardly through the aligned openings 58, 21 and 25 into the interior of the watercraft and provides the means for pivoting the gimbal ring member 38 and stern drive unit 1 in a generally horizontal plane for steering control of the unit.

The means for actuating the steering control arm 59 to effect steering control of the stern drive unit includes the telescopically related tubular members 60 and 61. Tubular member 60 is slidable within tubular member 61 and constitutes an extension of the core wire 62 of the steering control cable 63. A coupler element 64 is provided on the free end of member 60 and is adapted to pivotally receive one end of a link bar 65 on an axis generally normal to the axis of the coupler element and member 60. A pin member 66 is carried by the free end of steering arm 59 and generally parallels the steering axis. The opposite end of link bar 65 is universally mounted on pin member 66 to permit movement of the link bar in a manner to accommodate the forwardly raked steering axis.

The tubular member 61 constitutes an extension of casing 67 of cable 63 through the threaded fastener 68 and member 61 is xedly secured to the inner transom plate 19 within transversely aligned holes 69 provided in the transversely spaced projections 70 extending forwardly from plate 19. The member 61 is held in place by a pair of opposed nut members 71 disposed on a threaded portion of member 61 and adapted to engage the opposite faces of one of the projections 70. Steering control for the stern drive unit 1 is provided by actuation of the core wire 62 of cable 63 to move the tubular member 60 axially within member 61 to thereby actuate the steering lever arm 59 through the link bar 65 as generally shown in FIG. 3.

As further shown in FIG. 3, steering of the stern drive unit may be controlled through cable 63 from a remote location within the watercraft by means of steering wheel 72 which rotates the steering shaft 73 in the desired manner. The remote steering shaft 73 carries the gear 74 which meshes with a rack 75 slidably disposed in the gear housing 76. Steering cable 63 extends to the housing 76 and a threaded fastener element 77 xedly secures the cable casing 67 to the housing. The cable core wire 62 extends through the fastener element 77 and is secured to the rack 75 so that movements of the rack as effected by the steering wheel actuate the core wire of cable 63 tst; produce corresponding movement of the steering arm Since the steering arm 59 passes through the single transom mounting hole, an additional transom hole or holes is unnecessary to accommodate the steering mechanism. As a result installation is easier and less costly. The outboard steering arm enclosure 55 opening into the interior of the watercraft provides for a steering installat1on all parts of which remain inside the watercraft Where they are protected from damage and corrosion. Eliminated is the unsightly clutter of control mechanism passing through the transom at miscellaneous locations along with the associated costly attaching hardware.

Various modes of carrying out the invention are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention:

I claim:

l. In an inboard-outboard drive for watercraft having a transom, a propulsion unit including a generally vertical drlve shaft and disposed outboard of the watercraft, support means pivotally supporting the propulsion unit on a generally transverse horizontal axis for tilt movements in a generally vertical plane and including pivot means disposed on a generally vertical axis, enclosure means mounted on the transom and adapted to pivotally receive the pivot means of said support means placing the pivot means forwardly of said vertical drive shaft and having an opening forwardly thereof communicating with the interior of the watercraft, and means extending from the interior of the watercraft through said opening and secured to the pivot means of said support means to pivot the support means together with the propulsion unit in a generally horizontal plane to provide for steering control of said unit.

2. In an inboard-outboard drive for watercraft having a transom, a propulsion unit including a generally vertical drive shaft and disposed outboard of the watercraft, support means pivotally supporting the propulsion unit on a generally transverse horizontal axis for tilt movements in a generally vertical plane and having a generally vertical shaft, enclosure means mounted on the transom and having a generally vertical bore to pivotally receive the shaft of the support means placing the shaft forwardly of the vertical drive shaft, said enclosure means having an opening forwardly thereof in alignment with an opening in the transom placing the interior of the enclosure means and shaft therein in communication with the interior of the watercraft, and means extending through the aligned openings from the interior of the Watercraft and secured to the shaft to pivot the support means together with the propulsion unit in a generally horizontal plane to provide for steering control of said unit.

3. The invention of claim 2 wherein the propulsion unit support means is carried by a support member rigidly secured to the transom and the enclosure means receiving the generally vertical shaft on the support means is formed integrally with said support member.

4. In an inboard-outboard drive for watercraft having a transom, a propulsion unit including a generally vertical drive shaft and disposed outboard of the watercraft, a support member rigidly secured to the outboard side of the transom and including an enclosure having a generally vertically bore therein forwardly of the vertical drive shaft, a gimbal ring member pivotally supporting the propulsion unit on a generally transverse horizontal axis and being pivotally supported by the support member on a generally vertical axis with a generally vertical shaft portion on the gimbal ring member extending into the bore of the support member enclosure, said enclosure having an opening forwardly thereof in alignment with an opening in the transom to place the interior of the enclosure and References Cited in the le of this patent UNITED STATES PATENTS 1,028,333 Desenberg lune 4, 1912 1,980,685 Johnson Nov. 13, 1934 2,681,029 Canazzi June 15, 1954 2,961,986 Rockhill Nov. 29, 1960 3,006,311 Hansson et al. Oct. 31, 1961 

1. IN AN INBOARD-OUTBOARD DRIVE FOR WATERCRAFT HAVING A TRANSOM, A PROPULSION UNIT INCLUDING A GENERALLY VERTICAL DRIVE SHAFT AND DISPOSED OUTBOARD OF THE WATERCRAFT, SUPPORT MEANS PIVOTALLY SUPPORTING THE PROPULSION UNIT ON A GENERALLY TRANSVERSE HORIZONTAL AXIS FOR TILT MOVEMENTS IN A GENERALLY VERTICAL PLANE AND INCLUDING PIVOT MEANS DISPOSED ON A GENERALLY VERTICAL AXIS, ENCLOSURE MEANS MOUNTED ON THE TRANSOM AND ADAPTED TO PIVOTALLY RECEIVE THE PIVOT MEANS OF SAID SUPPORT MEANS PLACING THE PIVOT MEANS FORWARDLY OF SAID VERTICAL DRIVE SHAFT AND HAVING AN OPENING FORWARDLY THEREOF COMMUNICATING WITH THE INTERIOR OF THE WATERCRAFT, AND MEANS EXTENDING FROM THE INTERIOR OF THE WATERCRAFT THROUGH SAID OPENING AND SECURED TO THE PIVOT MEANS OF SAID SUPPORT MEANS TO PIVOT THE SUPPORT MEANS TOGETHER WITH THE PROPULSION UNIT IN A GENERALLY HORIZONTAL PLANE TO PROVIDE FOR STEERING CONTROL OF SAID UNIT. 